JP2019190355A - Saddle riding-type vehicle - Google Patents

Abstract

To properly keep detection accuracy of an oxygen sensor by suppressing the problem that an oxygen sensor is cooled by vehicle running-induced wind, in a saddle riding-type vehicle comprising the oxygen sensor disposed behind a fan cover.SOLUTION: The saddle riding-type vehicle comprises a sensor cover 65 which is formed integrally with a fan cover 61, and is disposed at a position more outward in a vehicle width direction than an oxygen sensor 50, overlaps on at least a part of the oxygen sensor 50 in a vehicle side view, and extends outward in the vehicle width direction and rearward in a vehicle longitudinal direction. A silencer cover 26 has a front portion 26a which is disposed at a position more outward in the vehicle width direction than the oxygen sensor 50, and extends outward in the vehicle width direction and rearward in the vehicle longitudinal direction. In a vehicle plane view, a distance ΔA in the vehicle longitudinal direction between a rear end 62e of the sensor cover 65 and a front end 26aa of a front portion 26a of the silencer cover 26 is shorter than a distance ΔB in the vehicle longitudinal direction between a rear end 61a of the fan cover 61 and a front end 25a of a silencer 25.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a saddle riding type vehicle.

  Conventionally, a saddle-ride type vehicle equipped with an oxygen sensor for detecting the oxygen concentration of exhaust gas is known. The oxygen sensor has a sensor element including a material such as zirconia. In order to detect the oxygen concentration with high accuracy, it is necessary to maintain the temperature of the sensor element at a predetermined activation temperature.

  Patent Document 1 describes a motorcycle in which an oxygen sensor is attached to a rear portion of a fan cover of an exhaust pipe. A fan is provided inside the fan cover, and an opening for introducing air is formed in the fan cover.

JP 2009-226988 A

  If the oxygen sensor is provided near the combustion chamber of the engine, the sensor element can be warmed early by the high-temperature exhaust gas from the combustion chamber. Further, it becomes easy to maintain the sensor element at a predetermined temperature. However, as disclosed in Patent Document 1, there are cases where the oxygen sensor needs to be provided at a position far from the combustion chamber when the arrangement of the oxygen sensor is considered. In this case, the influence of heat from the combustion chamber is reduced, and it takes time to warm the sensor element of the oxygen sensor. Further, it is difficult to stably maintain the temperature of the sensor element. Therefore, in the motorcycle disclosed in Patent Document 1, it is conceivable to use an oxygen sensor incorporating a heater for heating the sensor element.

  By the way, with the traveling of the motorcycle, wind flows from the front to the rear of the motorcycle. Hereinafter, this wind is referred to as “running wind”. Although an opening for introducing air is formed in the fan cover, the fan cover is provided at a position where the traveling wind passes so that air can be easily introduced during traveling of the motorcycle. Therefore, when the oxygen sensor is disposed in the vicinity of the fan cover, the oxygen sensor is easily cooled by the traveling wind. Therefore, even if the oxygen sensor has a built-in heater, the detection accuracy of the oxygen sensor may be reduced.

  The present invention has been made in view of such a point, and an object thereof is to suppress the oxygen sensor from being cooled by traveling wind in a straddle-type vehicle provided with an oxygen sensor disposed behind the fan cover. Thus, the detection accuracy of the oxygen sensor is kept good.

  In order to achieve the above object, the inventor of the present application has integrally formed a sensor cover on the fan cover that makes it difficult for the running air to hit the oxygen sensor. Specifically, the sensor cover is formed integrally with the rear part of the fan cover so that the sensor cover and at least a part of the oxygen sensor overlap in a side view of the vehicle. In addition, the portion of the sensor cover that overlaps the oxygen sensor is shaped to protrude outward in the vehicle width direction toward the rear. Thereby, it was considered that traveling air could be prevented from directly hitting the oxygen sensor and the traveling air could be smoothly guided backward.

  As a result of the above measures, the running wind no longer hits the oxygen sensor directly. However, a negative pressure is generated behind the sensor cover, so that the traveling wind after flowing along the surface of the sensor cover flows into the sensor cover due to the negative pressure and flows around the oxygen sensor. Will occur.

  Therefore, the inventor of the present application tried further investigation as follows. First, we examined increasing the size of the sensor cover to extend backward. However, when the sensor cover is enlarged, the force that the sensor cover receives from the traveling wind increases. Therefore, it is not preferable from the viewpoint of securing rigidity of the sensor cover and the fan cover integrated with the sensor cover.

  Therefore, the inventor of the present application paid attention to the silencer cover provided outside the silencer in the vehicle width direction. And even if the sensor cover is not enlarged, it is possible to make it difficult for the traveling wind flowing along the surface of the sensor cover to flow into the inside of the sensor cover by effectively arranging both the sensor cover and the silencer cover. It was possible that the oxygen sensor would be difficult to be cooled by the traveling wind. The configuration of the invention based on such knowledge is as follows.

  A straddle-type vehicle according to the present invention includes an internal combustion engine, an exhaust pipe connected to the internal combustion engine, a silencer disposed behind the exhaust pipe and connected to the exhaust pipe, and a vehicle width of the internal combustion engine. A fan disposed outward in the direction, a fan cover disposed outward in the vehicle width direction of the fan and formed with an opening, and a silencer cover disposed outward in the vehicle width direction of the silencer, A sensor element disposed inside the exhaust pipe and a heater for heating the sensor element; the oxygen sensor attached to the exhaust pipe; and the fan cover; A sensor cover that is located outward in the vehicle width direction, overlaps at least a part of the oxygen sensor in a side view of the vehicle, and extends outward in the vehicle width direction and rearward in the vehicle front-rear direction. The silencer cover has a front portion that is located outward in the vehicle width direction from the oxygen sensor and extends outward in the vehicle width direction and rearward in the vehicle front-rear direction. In the vehicle plan view, the distance in the vehicle longitudinal direction between the rear end of the sensor cover and the front end of the front portion of the silencer cover is the vehicle longitudinal direction between the rear end of the fan cover and the front end of the silencer. Shorter than the distance.

  According to the saddle-ride type vehicle, the traveling wind flows around the oxygen sensor due to the negative pressure by the sensor cover and the front part of the silencer cover while preventing the traveling wind from directly hitting the oxygen sensor. Can be suppressed. Therefore, it can suppress that an oxygen sensor is cooled with driving | running | working wind, and can maintain the detection accuracy of an oxygen sensor favorable.

  According to a preferred aspect of the present invention, in the vehicle plan view, the inner end in the vehicle width direction of the front portion of the silencer cover is more inward in the vehicle width direction than the outer end in the vehicle width direction of the sensor cover. positioned.

  According to a preferred aspect of the present invention, the front end of the front portion of the silencer cover is positioned more inward in the vehicle width direction than the outer end of the sensor cover in the vehicle width direction in plan view of the vehicle.

  According to each said aspect, it can further suppress that driving | running | working wind flows around the oxygen sensor by a negative pressure.

  According to a preferred aspect of the present invention, the front end of the front portion of the silencer cover is located at the same position as the rear end of the sensor cover or forward of the rear end of the sensor cover in the vehicle longitudinal direction. ing.

  According to the said aspect, it can further suppress that driving | running | working wind flows into the circumference | surroundings of an oxygen sensor by a negative pressure.

  According to a preferred aspect of the present invention, the oxygen sensor is arranged behind the internal combustion engine.

  According to a preferred aspect of the present invention, the saddle riding type vehicle includes a rear wheel driven by the internal combustion engine, and at least a part of the oxygen sensor is disposed at a position overlapping the rear wheel in a side view of the vehicle. Has been.

  According to a preferred aspect of the present invention, the straddle-type vehicle includes a catalyst that purifies the exhaust gas flowing through the exhaust pipe, and the oxygen sensor is disposed downstream of the catalyst in the flow direction of the exhaust gas. Yes.

  According to each of the above aspects, since the oxygen sensor is disposed at a position far from the internal combustion engine, the above-described effect becomes remarkable.

  According to a preferred aspect of the present invention, the sensor cover is disposed behind the opening of the fan cover.

  According to the above aspect, a part of the traveling wind can be supplied to the fan through the opening of the fan cover, and the other part of the traveling wind is smoothly guided backward by the sensor cover so as not to hit the oxygen sensor. be able to.

  According to a preferred aspect of the present invention, the oxygen sensor has a cylindrical case located outside the exhaust pipe. In a vehicle side view, the minimum distance in the vehicle front-rear direction between the sensor cover and the front portion of the silencer cover is smaller than the dimension of the oxygen sensor in the axial direction of the case.

  According to the above aspect, since the minimum distance in the vehicle front-rear direction between the sensor cover and the front part of the silencer cover is small, it is possible to further suppress the traveling wind from flowing around the oxygen sensor due to negative pressure. .

  According to a preferred aspect of the present invention, in the vehicle side view, the sensor cover is formed with a recessed portion that is recessed forward, and the front portion of the silencer cover projects forward toward the recessed portion. Protrusions are formed.

  According to the said aspect, the sensor cover and the front part of a silencer cover are formed in the shape which mutually adapted in the vehicle side view. Therefore, it is possible to effectively suppress the traveling wind flowing along the surface of the sensor cover from flowing into the inside of the sensor cover, and to effectively suppress the oxygen sensor from being cooled by the traveling wind. it can.

  According to a preferred aspect of the present invention, the oxygen sensor has a wire connecting portion. The saddle riding type vehicle includes an electric wire connected to the electric wire connecting portion.

  According to a preferred aspect of the present invention, the sensor cover overlaps the electric wire connecting portion of the oxygen sensor in a vehicle side view.

  According to the said aspect, the electric wire connection part of an oxygen sensor can be protected by a sensor cover.

  According to a preferred aspect of the present invention, the straddle-type vehicle is formed integrally with the fan cover, and is located outward in the vehicle width direction of at least a part of the electric wire, and in a vehicle side view. An electric wire cover that overlaps at least a part of the electric wire is provided.

  According to the said aspect, at least one part of an electric wire can be protected by an electric wire cover.

  According to a preferred aspect of the present invention, the oxygen sensor has a sensor element located inside the exhaust pipe. The wire connecting portion is disposed above the sensor element in the vehicle vertical direction and in the vehicle width direction.

  According to the said aspect, since the electric wire connection part is arrange | positioned upwards rather than a sensor element, the maintenance of an oxygen sensor is easy. Moreover, since the electric wire connection part is arrange | positioned inside the vehicle width direction rather than the sensor element, it can avoid that an electric wire connection part protrudes to the outward of a vehicle width direction.

  According to a preferred aspect of the present invention, the electric wire includes an electric wire portion that is disposed above the fan and inward of the fan cover in the vehicle width direction and extends forward.

  By the said aspect, the arrangement | positioning of an electric wire becomes easy.

  According to a preferred aspect of the present invention, the saddle riding type vehicle includes a radiator disposed between the fan cover and the fan.

  According to the present invention, in a saddle-ride type vehicle equipped with an oxygen sensor disposed behind the fan cover, the oxygen sensor is prevented from being cooled by the traveling wind, thereby maintaining good detection accuracy of the oxygen sensor. be able to.

It is a right view of the scooter which concerns on embodiment. It is a right view of the above-mentioned scooter when a front cover and a side cover are removed. It is a bottom view of the scooter. It is a top view of a part of the scooter. It is a front view of a part of the scooter. It is a perspective view of a cover. It is a right view of a part of the scooter. It is a front view of a part of the scooter. FIG. 8B is a view corresponding to FIG. It is sectional drawing of a 2nd oxygen sensor and a 2nd exhaust pipe, Comprising: The cross section containing the center line of a 2nd oxygen sensor and perpendicular | vertical to the center line of a 2nd exhaust pipe is represented. FIG. 5 is a plan view of a part of the scooter for explaining traveling wind flowing along a sensor cover and a silencer cover. FIG. 11 is a diagram corresponding to FIG. 10 when it is assumed that there is no sensor cover. FIG. 11 is a view corresponding to FIG. 10 when the distance in the vehicle front-rear direction between the rear end of the sensor cover and the front end of the front portion of the silencer cover is long.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, the saddle riding type vehicle according to the present embodiment is a scooter 1 including an oxygen sensor 50 that detects the oxygen concentration of exhaust gas.

  The scooter 1 includes a seat 2 on which an occupant sits. In the following description, unless otherwise specified, front, rear, left, right, upper, and lower refer to a scooter 1 in which an occupant is not in the vehicle, is not loaded with luggage, and is not filled with fuel. When the vehicle is stopped in this state, it means front, rear, left, right, upper, and lower viewed from a virtual occupant seated on the seat 2, respectively. F, Re, L, R, U, and D in the figure represent front, rear, left, right, upper, and lower, respectively.

  FIG. 2 is a side view of the scooter 1 when a front cover 28, a side cover 29 and the like which will be described later are removed. As shown in FIGS. 1 and 2, the scooter 1 includes a body frame 3, a front wheel 35, a rear wheel 36, a footboard 4, and a pivot shaft 6 provided on the body frame 3. The foot board 4 is supported by the vehicle body frame 3, and at least a part of the foot board 4 is disposed behind the front wheel 35. The scooter 1 includes a front cover 28 at least partially located below the head pipe 3A of the vehicle body frame 3, a side cover 29 disposed outside the vehicle body frame 3 in the vehicle width direction, a front cover 28, The under cover 5 is provided below the side cover 29. At least a part of the under cover 5 is disposed below the foot board 4 and behind the front wheel 35. The engine unit 10 is swingably supported on the pivot shaft 6, and at least a part of the engine unit 10 is disposed below the footboard 4.

  As shown in FIG. 2, the engine unit 10 includes an internal combustion engine 11A. The internal combustion engine 11A includes a crankcase 11, a cylinder body 12 connected to the crankcase 11, and a cylinder head connected to the cylinder body 12. 13. Although illustration is omitted, the crankshaft of the internal combustion engine 11 </ b> A is disposed inside the crankcase 11. The cylinder body 12 is disposed in front of the crankcase 11, and the cylinder head 13 is disposed in front of the cylinder body 12. The cylinder head 13 has an exhaust port 14 through which exhaust gas is discharged.

  The engine unit 10 includes a transmission case 7 (see FIG. 3) disposed on the left side of the rear wheel 36 and a belt-type continuously variable transmission (hereinafter referred to as CVT) (not shown) disposed in the transmission case 7. And). The CVT is connected to the crankshaft of the internal combustion engine 11A and the rear wheel 36, and transmits the torque of the crankshaft to the rear wheel 36 so that the gear ratio can be changed. The rear wheel 36 is driven by the internal combustion engine 11A. As shown in FIG. 4, a rear arm 8 that connects the crankcase 11 and the rear wheel 36 is disposed to the right of the rear wheel 36. The rear wheel 36 is supported by the engine unit 10 and the rear arm 8 and swings together with the engine unit 10 and the rear arm 8. A rear cushion unit 9 is provided between the vehicle body frame 3 and the rear arm 8 (see FIG. 2). When the engine unit 10 swings upward, the rear cushion unit 9 contracts, and when the engine unit 10 swings downward, the rear cushion unit 9 expands.

  In the present embodiment, the internal combustion engine 11A of the engine unit 10 is water-cooled. As shown in FIGS. 4 and 5, a fan 16 is disposed on the right side of the crankcase 11, and a radiator 15 is disposed on the right side of the fan 16.

  As shown in FIG. 1, a cover 60 is disposed on the right side of the radiator 15. FIG. 6 is a perspective view of the cover 60. As will be described in detail later, the cover 60 includes a fan cover 61, a lower extension cover 62 that extends rearward from the lower portion of the fan cover 61, and an upper extension cover 63 that extends rearward from the upper portion of the fan cover 61. The cover 60 is a single component, and the fan cover 61, the lower extension cover 62, and the upper extension cover 63 are integrally formed.

  The fan cover 61 is a cover in a region overlapping with the fan 16 in a vehicle side view. In other words, the fan cover 61 is a cover located directly beside the fan 16. In FIG. 6, the outline of the fan 16 is indicated by a broken line. In the present embodiment, in the cover 60, a portion on the contour line and a portion on the inner side of the contour line correspond to the fan cover 61 in the vehicle side view. A plurality of openings 17 a and 17 b are formed in the fan cover 61. Here, the fan cover 61 is formed with five front openings 17a arranged vertically and three rear openings 17b arranged vertically. However, the openings 17a and 17b are merely examples, and the number, shape, and position of the opening of the fan cover 61 are not limited.

  When an impeller (not shown) of the fan 16 rotates, air is supplied to the radiator 15 through the openings 17 a and 17 b of the fan cover 61. Since the fan 16, the radiator 15, and the cover 60 are supported by the crankcase 11, they swing together with the engine unit 10. Note that the internal combustion engine 11A of the engine unit 10 is not necessarily water-cooled. The internal combustion engine 11A may be air-cooled, and the radiator 15 may not be provided.

  The lower extension cover 62 includes an upper edge portion 62a and a lower edge portion 62b that respectively extend rearward, and a rear edge portion 62c that extends from the rear end of the upper edge portion 62a to the rear end of the lower edge portion 62b. The rear edge portion 62c includes an upper portion 62c1 extending forward and downward from the rear end of the upper edge portion 62a, and a lower portion 62c2 extending forward and upward from the rear end of the lower edge portion 62b, and is concave toward the front. Is formed.

  The upper extension cover 63 includes an upper edge portion 63a that extends rearward and downward, and a lower edge portion 63b that extends rearward and upward. The upper extension cover 63 is formed in a convex shape toward the rear. However, the shape of the upper extension cover 63 is only an example, and is not particularly limited. Further, the upper extension cover 63 is not necessarily required and can be omitted.

  As shown in FIG. 1, the scooter 1 includes an exhaust pipe 24 and a silencer 25. The exhaust pipe 24 includes a first exhaust pipe 21, a catalyst case 23 in which the catalyst 20 is accommodated, and a second exhaust pipe 22. A silencer cover 26 is disposed on the side of the silencer 25. The first exhaust pipe 21, the catalyst case 23, the second exhaust pipe 22, the silencer 25, and the silencer cover 26 are configured to swing integrally with the engine unit 10.

  As shown in FIG. 3, the upstream end 21 a of the first exhaust pipe 21 is connected to the exhaust port 14 of the cylinder head 13. The first exhaust pipe 21 and the catalyst case 23 are connected by a first pipe joint 31. The catalyst case 23 and the second exhaust pipe 22 are connected by a second pipe joint 32. The second exhaust pipe 22 and the silencer 25 are connected by a third pipe joint 33.

  The first exhaust pipe 21 is a metal pipe. The first exhaust pipe 21 is disposed below the engine unit 10. As shown in FIG. 3, the first exhaust pipe 21 is disposed so as to overlap the engine unit 10 in the vehicle bottom view.

  The second exhaust pipe 22 is also a metal pipe. The second exhaust pipe 22 extends rearward and outward in the vehicle width direction as viewed from the bottom of the vehicle. As shown in FIG. 1, the second exhaust pipe 22 extends rearward and upward in a vehicle side view.

  The catalyst case 23 is formed of a metal cylinder. However, the shape of the catalyst case 23 is not particularly limited. The catalyst 20 is disposed inside the catalyst case 23. The catalyst 20 is disposed inside the exhaust pipe 24 and purifies the exhaust gas flowing through the exhaust pipe 24. The catalyst case 23 is disposed in front of the rear wheel 36, and the catalyst 20 is disposed in front of the rear wheel 36. The inner diameter of the catalyst case 23 is larger than the inner diameter of each of the first exhaust pipe 21 and the second exhaust pipe 22. Further, the outer diameter of the catalyst case 23 is larger than the outer diameter of either the first exhaust pipe 21 or the second exhaust pipe 22. As shown in FIG. 3, when viewed from the bottom of the vehicle, the catalyst case 23 extends rearward and outward in the vehicle width direction. As shown in FIG. 1, the catalyst case 23 extends rearward in a vehicle side view. However, the installation posture of the catalyst case 23 is not particularly limited.

  As shown in FIG. 7, a first oxygen sensor 40 is attached to the first exhaust pipe 21. The first oxygen sensor 40 is disposed on the upstream side of the catalyst 20 and detects the oxygen concentration of the exhaust gas before being purified by the catalyst 20. Based on the oxygen concentration of the exhaust gas detected by the first oxygen sensor 40, the air-fuel ratio of the exhaust gas discharged from the internal combustion engine 11A can be detected. Therefore, the internal combustion engine 11A can be controlled based on the detection result of the first oxygen sensor 40 so that a predetermined combustion state is obtained.

  As shown in FIG. 3, the first oxygen sensor 40 is attached to a portion closer to the catalyst 20 than an intermediate position (position indicated by a broken line in FIG. 3) 21 m of the first exhaust pipe 21. The intermediate position of the first exhaust pipe 21 is an intermediate position between the upstream end 21a and the downstream end 21b in the direction along the center line of the first exhaust pipe 21. The first oxygen sensor 40 is disposed behind the cylinder body 12 of the engine unit 10. The first oxygen sensor 40 is disposed behind the pivot shaft 6 that supports the engine unit 10 so as to be swingable.

  As shown in FIG. 7, the first exhaust pipe 21 is provided with an attachment portion 43 for attaching the first oxygen sensor 40. The attachment portion 43 is formed in a cylindrical shape and is welded to the first exhaust pipe 21.

  As shown in FIG. 1, the first oxygen sensor 40 is not covered by the side cover 29 and exposed in a side view of the vehicle. The first oxygen sensor 40 is arranged so as to be visually recognized when the scooter 1 is viewed from the right side. As shown in FIG. 3, the first oxygen sensor 40 overlaps with the crankcase 11 but does not overlap with the under cover 5 in the vehicle bottom view. When viewed from the bottom of the vehicle, at least a portion of the first oxygen sensor 40 is disposed to the right of the left end 35L of the front wheel 35 and to the left of the right end 35R. The first oxygen sensor 40 is disposed near the center of the vehicle.

  As shown in FIG. 7, a second oxygen sensor 50 is attached to the second exhaust pipe 22. The second oxygen sensor 50 is disposed on the downstream side of the catalyst 20 and detects the oxygen concentration of the exhaust gas after being purified by the catalyst 20. When the catalyst 20 is deteriorated, the exhaust gas is not properly purified. Therefore, based on the detection result of the second oxygen sensor 50, it can be detected whether or not the catalyst 20 has deteriorated. The deterioration of the catalyst 20 may be detected by comparing the detection result of the first oxygen sensor 40 with the detection result of the second oxygen sensor 50.

  As shown in FIG. 7, the second exhaust pipe 22 is provided with an attachment portion 54 for attaching the second oxygen sensor 50. The attachment portion 54 is formed in a cylindrical shape and is welded to the second exhaust pipe 22.

  As shown in FIG. 2, the second oxygen sensor 50 is disposed behind the internal combustion engine 11 </ b> A of the engine unit 10. As shown in FIG. 7, at least a part of the second oxygen sensor 50 is disposed at a position overlapping the rear wheel 36 in a vehicle side view.

  As shown in FIG. 9, the second oxygen sensor 50 includes a sensor element 51 located inside the second exhaust pipe 22, a cylindrical case 52 located outside the second exhaust pipe 22, and the sensor element 51. And a heater 53 for heating. The sensor element 51 includes a material such as zirconia. The heater 53 is built in the second oxygen sensor 50.

  As shown in FIG. 9, in a cross section including the center line 50 </ b> C of the second oxygen sensor 50 and perpendicular to the center line 22 </ b> C of the second exhaust pipe 22, at least a part of the case 52 is centered on the second exhaust pipe 22. It is arranged inward and upward in the vehicle width direction from 22C. However, the installation posture of the 2nd oxygen sensor 50 demonstrated here is an example, and is not necessarily limited. In addition, the inside in the vehicle width direction refers to a direction approaching the vehicle center line CL, and the outside in the vehicle width direction refers to a direction away from the vehicle center line CL (see FIG. 3).

  As shown in FIG. 1, a first electric wire 45 is connected to the first oxygen sensor 40. A part of the first electric wire 45 is exposed in a side view of the vehicle. A part of the first electric wire 45 is visible when viewed from the right side. Therefore, when the maintenance or the like of the first oxygen sensor 40 is performed, the first electric wire 45 can be easily handled from the right side, and the maintenance of the first oxygen sensor 40 is easy. The first electric wire 45 extends upward from the first oxygen sensor 40 and then extends forward. The first electric wire 45 does not pass below the engine unit 10. The first electric wire 45 is connected to an ECU (Electronic Control Unit) (not shown).

  As shown in FIG. 9, the second oxygen sensor 50 has a wire connection portion 55, and the second wire 46 is connected to the wire connection portion 55. The electric wire connection portion 55 is disposed above the sensor element 51 in the vehicle vertical direction and inward in the vehicle width direction. As shown in FIG. 7, the second electric wire 46 extends upward from the second oxygen sensor 50 and then extends forward. The second electric wire 46 passes above the fan 16. A part 46 a of the second electric wire 46 is disposed above the fan 16. The second electric wire 46 does not pass below the engine unit 10. The second electric wire 46 is connected to the ECU.

  As shown in FIGS. 8A and 8B, the first oxygen sensor 40, the second oxygen sensor 50, and the under cover 5 overlap each other when the vehicle is viewed from the front. The first oxygen sensor 40 and the second oxygen sensor 50 are arranged so as not to be visually recognized when the scooter 1 is viewed from the front.

  As shown in FIG. 7, a part of the lower extension cover 62 overlaps at least a part of the second oxygen sensor 50 in a side view of the vehicle. In the present embodiment, the part of the lower extension cover 62 constitutes a sensor cover 65. The sensor cover 65 is disposed behind the openings 17 a and 17 b of the fan cover 61. As shown in FIG. 4, the sensor cover 65 is located outward of the second oxygen sensor 50 in the vehicle width direction. The lower extension cover 62 extends outward in the vehicle width direction and rearward in the vehicle front-rear direction, and the sensor cover 65 extends outward in the vehicle width direction and rearward in the vehicle front-rear direction.

  The silencer cover 26 is disposed outside the silencer 25 in the vehicle width direction. The front portion 26 a of the silencer cover 26 is located outward of the second oxygen sensor 50 in the vehicle width direction. Further, the front portion 26a of the silencer cover 26 extends outward in the vehicle width direction and rearward in the vehicle front-rear direction, and is curved in this embodiment.

  In the present embodiment, as shown in FIG. 4, the rear end 62 d of the lower extension cover 62 and the front end 26 aa of the front portion 26 a of the silencer cover 26 are at the same position in the vehicle front-rear direction. In a vehicle plan view, if a straight line passing through the rear end 62d of the lower extension cover 62 and extending in the vehicle width direction is L1, and a straight line L2 passing through the front end 26aa of the front portion 26a of the silencer cover 26 and extending in the vehicle width direction, the straight line L1 And the straight line L2 coincide with each other. If the distance in the vehicle front-rear direction between the rear end 62d of the lower extension cover 62 and the front end 26aa of the front portion 26a of the silencer cover 26 is ΔA, ΔA = 0 in this embodiment. In FIG. 7, reference numeral 61 a represents the rear end of the fan cover 61. In FIG. 4, symbol L3 represents a straight line that passes through the rear end 61a of the fan cover 61 and extends in the vehicle width direction in a vehicle plan view. Reference sign L4 represents a straight line that passes through the front end 25a of the silencer 25 and extends in the vehicle width direction in a plan view of the vehicle. In the vehicle plan view, a distance in the vehicle front-rear direction between the rear end 61a of the fan cover 61 and the front end 25a of the silencer 25 is denoted by ΔB. Then, ΔA <ΔB.

  In FIG. 4, a symbol L <b> 5 represents a straight line extending in the vehicle front-rear direction through the inner end 26 ae in the vehicle width direction of the front portion 26 a of the silencer cover 26 in the vehicle plan view. Reference symbol L6 represents a straight line that passes through the outer end 62e of the lower extension cover 62 in the vehicle width direction and extends in the vehicle front-rear direction in plan view of the vehicle. Here, the straight line L5 is located more inward in the vehicle width direction than the straight line L6. That is, in the vehicle plan view, the inner end 26ae in the vehicle width direction of the front portion 26a of the silencer cover 26 is located inward in the vehicle width direction than the outer end 62e in the vehicle width direction of the lower extension cover 62.

  In the present embodiment, as described above, the front end 26aa of the front portion 26a of the silencer cover 26 is at the same position as the rear end 62d of the lower extension cover 62 in the vehicle longitudinal direction, but the positional relationship is not particularly limited. With respect to the vehicle front-rear direction, the front end 26aa of the front portion 26a of the silencer cover 26 may be positioned forward of the rear end 62d of the lower extension cover 62, and ΔA> 0 may be satisfied. Even when ΔA> 0, it is preferable that ΔA <ΔB.

  As shown in FIG. 7, the sensor cover 65 and the front portion 26 a of the silencer cover 26 are formed in shapes that are compatible with each other in a vehicle side view. Here, when viewed from the side of the vehicle, the sensor cover 65 is formed with a concave portion 65a that is recessed forward, and the front portion 26a of the silencer cover 26 is formed with a convex portion 26ab that protrudes forward toward the concave portion 65a. ing.

  When viewed from the side of the vehicle, an interval is provided between the sensor cover 65 and the front portion 26a of the silencer cover 26 in the vehicle front-rear direction, but the interval is relatively small. Although the interval varies depending on the vertical position, the minimum interval G1 among these intervals is smaller than the dimension F1 in the axial direction of the case 52 of the second oxygen sensor 50 (see FIG. 9). However, this is an example, and the minimum gap G1 is not particularly limited.

  The sensor cover 65 overlaps the electric wire connection portion 55 of the second oxygen sensor 50 in a vehicle side view. A part of the second electric wire 46 overlaps the sensor cover 65 in a vehicle side view. The other part of the second electric wire 46 is located inward in the vehicle width direction of the upper extension cover 63 of the cover 60 and overlaps the upper extension cover 63 in a side view of the vehicle. A part of the upper extension cover 63 constitutes an electric wire cover 66. A portion 46a of the second electric wire 46 is disposed above the fan 16 and inward in the vehicle width direction from the fan cover 61, and extends forward.

  The above is the configuration of the scooter 1. Next, the influence of traveling wind on the second oxygen sensor 50 will be described.

  When the scooter 1 travels, wind (that is, travel wind) W flows from the front to the rear as shown in FIG. The fan cover 61 is disposed at a position where the traveling wind W hits so that air can be easily introduced into the openings 17a and 17b (see FIG. 6). In the present embodiment, the second oxygen sensor 50 is disposed in the vicinity of the fan cover 61. Here, as shown in FIG. 11, when it is assumed that there is no sensor cover 65, the traveling wind W1 that flows along the fan cover 61 flows toward the second oxygen sensor 50, and cools the second oxygen sensor 50. End up. In this case, the second oxygen sensor 50 has a built-in heater 53 (see FIG. 9), but the temperature of the sensor element 51 is lowered and the detection accuracy may be lowered.

  However, according to the present embodiment, the sensor cover 65 formed integrally with the fan cover 61 is disposed outside the second oxygen sensor 50 in the vehicle width direction. Therefore, it is possible to prevent the traveling wind W1 from directly hitting the second oxygen sensor 50. On the other hand, as shown in FIG. 12, when the distance ΔA in the vehicle front-rear direction between the rear end 65d of the sensor cover 65 and the front end 26aa of the front portion 26a of the silencer cover 26 is large, negative pressure is applied to the rear of the sensor cover 65. As a result, there arises a problem that the traveling wind W <b> 2 flowing along the surface of the sensor cover 65 flows into the sensor cover 65 due to the negative pressure and flows around the second oxygen sensor 50.

  However, according to the present embodiment, the distance ΔA in the vehicle front-rear direction between the rear end 65d of the sensor cover 65 and the front end 26aa of the front portion 26a of the silencer cover 26 is small and zero (see FIG. 4). In addition, the sensor cover 65 and the front portion 26a of the silencer cover 26 both extend outward in the vehicle width direction and rearward in the vehicle front-rear direction. Therefore, as shown in FIG. 10, the traveling wind W <b> 3 that flows along the surface of the sensor cover 65 tends to flow backward along the surface of the front portion 26 a of the silencer cover 26 as it is. As described above, according to the present embodiment, the sensor cover 65 and the silencer cover 26 cooperate to suppress the traveling wind from flowing toward the second oxygen sensor 50.

  As described above, according to the scooter 1 according to the present embodiment, it is possible to suppress the traveling wind from flowing toward the second oxygen sensor 50, and thus the second oxygen sensor 50 is cooled by the traveling wind. This can be suppressed. Therefore, the temperature drop of the sensor element 51 can be suppressed, and the detection accuracy of the second oxygen sensor 50 can be kept good.

  Although the positional relationship between the sensor cover 65 and the front portion 26a of the silencer cover 26 is not particularly limited, in the present embodiment, as shown in FIG. 4, the inner end of the front portion 26a of the silencer cover 26 in the vehicle width direction in the vehicle plan view. 26ae is located inward in the vehicle width direction from the outer end 62e of the sensor cover 65 in the vehicle width direction. Further, according to the present embodiment, the front end 26aa of the front portion 26a of the silencer cover 26 is located inward in the vehicle width direction with respect to the outer end 62e in the vehicle width direction of the sensor cover 65 in the vehicle plan view. . According to the present embodiment, since the sensor cover 65 and the front portion 26a of the silencer cover 26 are in the positional relationship as described above, it is further suppressed that the traveling wind flows around the second oxygen sensor 50 due to negative pressure. can do.

  In the present embodiment, the front end 26aa of the front portion 26a of the silencer cover 26 is at the same position as the rear end 62d of the sensor cover 65 in the vehicle front-rear direction. ΔA = 0. Thereby, it is possible to further suppress the traveling wind from flowing around the second oxygen sensor 50 due to the negative pressure.

  By the way, if the second oxygen sensor 50 is disposed near the exhaust port 14 of the internal combustion engine 11A of the engine unit 10, the second oxygen sensor 50 is heated by the high-temperature exhaust gas immediately after being discharged from the exhaust port 14. The In that case, the temperature of the sensor element 51 of the second oxygen sensor 50 is unlikely to decrease. However, according to this embodiment, as shown in FIG. 2, the second oxygen sensor 50 is disposed behind the internal combustion engine 11 </ b> A of the engine unit 10. Further, the second oxygen sensor 50 is disposed rearward so that at least a part of the second oxygen sensor 50 overlaps the rear wheel 36 in a side view of the vehicle. The second oxygen sensor 50 is arranged downstream of the catalyst 20 in the exhaust gas flow direction. According to the present embodiment, the second oxygen sensor 50 is disposed at a position far from the exhaust port 14 and is located in the vicinity of the fan cover 61, so that the second oxygen sensor 50 is suppressed by suppressing the temperature drop of the sensor element 51. The above-described effect of maintaining good detection accuracy of the sensor 50 is particularly remarkable.

  Further, according to the present embodiment, as shown in FIG. 7, the sensor cover 65 is disposed behind the openings 17 a and 17 b of the fan cover 61. Therefore, a part of the traveling wind can be supplied to the fan 16 through the openings 17a and 17b, and the other part of the traveling wind can be smoothly and rearwardly prevented from hitting the second oxygen sensor 50 by the sensor cover 65. Can lead.

  Further, according to the present embodiment, in the vehicle side view, the minimum distance G1 in the vehicle longitudinal direction between the sensor cover 65 and the front portion 26a of the silencer cover 26 is in the axial direction of the case 52 of the second oxygen sensor 50. It is smaller than the dimension F1 (see FIG. 9). Thus, since the minimum distance G1 in the vehicle front-rear direction between the sensor cover 65 and the front portion 26a of the silencer cover 26 is small, it is further possible that the traveling wind flows around the second oxygen sensor 50 due to negative pressure. Can be suppressed.

  Further, according to the present embodiment, the sensor cover 65 is formed with the recessed portion 65a that is recessed forward, and the front portion 26a of the silencer cover 26 protrudes forward toward the recessed portion 65a in a side view of the vehicle. A convex portion 26ab is formed. The sensor cover 65 and the front portion 26a of the silencer cover 26 are formed in shapes that are compatible with each other in a vehicle side view. Therefore, it is possible to effectively suppress the traveling wind flowing along the surface of the sensor cover 65 from flowing into the inside of the sensor cover 65, and to effectively cool the second oxygen sensor 50 by the traveling wind. Can be suppressed.

  According to the present embodiment, the sensor cover 65 overlaps the electric wire connection portion 55 of the second oxygen sensor 50 in a vehicle side view. Therefore, the electric wire connecting portion 55 of the second oxygen sensor 50 can be protected by the sensor cover 65.

  Further, according to the present embodiment, the cover 60 is located at the outer side in the vehicle width direction of at least a part of the second electric wire 46 and overlaps with at least a part of the second electric wire 46 in a side view of the vehicle. 66. Therefore, at least a part of the second electric wire 46 can be protected by the electric wire cover 66.

  Further, according to the present embodiment, as shown in FIG. 9, the electric wire connection portion 55 of the second oxygen sensor 50 is disposed above the sensor element 51 in the vehicle vertical direction and in the vehicle width direction. Thus, since the wire connection part 55 is arrange | positioned above the sensor element 51, the maintenance of the 2nd oxygen sensor 50 is easy. Moreover, since the electric wire connection part 55 is arrange | positioned inside the vehicle width direction rather than the sensor element 51, it can avoid that the electric wire connection part 55 protrudes to the outward of a vehicle width direction.

  Further, according to the present embodiment, as shown in FIG. 7, the second electric wire 46 is disposed above the fan 16 and inward in the vehicle width direction than the fan cover 61, and has a portion 46 a extending forward. Have. Therefore, the arrangement of the second electric wires 46 becomes easy.

  As mentioned above, although one Embodiment of this invention was described, of course, this invention is not limited to the said embodiment.

  In the embodiment, the transmission case 7 of the engine unit 10 is disposed on the left side of the vehicle center line CL, and the second oxygen sensor 50, the cover 60, and the silencer cover 26 are disposed on the right side of the vehicle center line CL. However, the transmission case 7 may be disposed on the right side of the vehicle center line CL, and the second oxygen sensor 50, the cover 60, and the silencer cover 26 may be disposed on the left side of the vehicle center line CL.

  In the embodiment, at least a part of the second oxygen sensor 50 is disposed at a position overlapping the rear wheel 36 in the vehicle side view, but the entire second oxygen sensor 50 overlaps the rear wheel 36 in the vehicle side view. It does not have to be.

  In the embodiment, the second oxygen sensor 50 is disposed on the downstream side of the catalyst 20, but the position of the second oxygen sensor 50 is not particularly limited. The second oxygen sensor 50 may be disposed on the upstream side of the catalyst 20.

  In the embodiment, the sensor cover 65 is disposed behind the openings 17 a and 17 b of the fan cover 61, but part or all of the sensor cover 65 is disposed behind the openings 17 a and 17 b of the fan cover 61. It does not have to be.

  In the embodiment, the sensor cover 65 is formed with the concave portion 65a, the silencer cover 26 is formed with the convex portion 26ab, and the sensor cover 65 and the front portion 26a of the silencer cover 26 are compatible with each other in a side view of the vehicle. It has a shape to However, the sensor cover 65 and the front portion 26a of the silencer cover 26 may have shapes that are not compatible with each other in a vehicle side view.

  In the embodiment, the sensor cover 65 overlaps the electric wire connecting portion 55 of the second oxygen sensor 50 in a vehicle side view, but is not particularly limited. The sensor cover 65 may not overlap with a part or all of the second oxygen sensor 50 in a vehicle side view.

  In the embodiment, the cover 60 includes the electric wire cover 66 that overlaps at least a part of the second electric wire 46 in a vehicle side view. However, the cover 60 may not have such a wire cover 66.

  The installation posture of the second oxygen sensor 50 is not particularly limited. It is also possible to arrange the electric wire connecting portion 55 below the sensor element 51 in the vehicle vertical direction. It is also possible to arrange the electric wire connecting portion 55 outside the sensor element 51 in the vehicle width direction.

  In the above-described embodiment, the internal combustion engine 11 </ b> A of the engine unit 10 is water-cooled, and the scooter 1 includes the radiator 15. However, the internal combustion engine 11A may be air-cooled. The scooter 1 may not include the radiator 15. The fan 16 may be configured to supply air to the internal combustion engine 11A.

  A straddle-type vehicle is a vehicle on which an occupant rides. The straddle-type vehicle is not limited to the scooter 1. The saddle riding type vehicle may be another type of motorcycle. The straddle-type vehicle may be a vehicle other than a motorcycle, for example, an automatic tricycle or an ATV (All Terrain Vehicle).

  The terms and expressions used herein are used for explanation and are not used for limited interpretation. It should be recognized that any equivalents of the features shown and described herein are not excluded and that various modifications within the claimed scope of the invention are permitted. The present invention can be embodied in many different forms. This disclosure should be regarded as providing embodiments of the principles of the invention. The embodiments are described herein with the understanding that the embodiments are not intended to limit the invention to the preferred embodiments described and / or illustrated herein. It is not limited to the embodiment described here. The present invention encompasses any embodiment that includes equivalent elements, modifications, deletions, combinations, improvements and / or changes that may be recognized by those skilled in the art based on this disclosure. Claim limitations should be construed broadly based on the terms used in the claims and should not be limited to the embodiments described herein or in the process of this application.

  DESCRIPTION OF SYMBOLS 1 ... Scooter, 10 ... Engine unit, 15 ... Radiator, 16 ... Fan, 17a, 17b ... Opening, 20 ... Catalyst, 24 ... Exhaust pipe, 25 ... Silencer, 26 ... Silencer cover, 26a ... Front part of silencer cover, 35 ... front wheel, 36 ... rear wheel, 46 ... second electric wire (electric wire), 46a ... electric wire part, 50 ... second oxygen sensor (oxygen sensor), 51 ... sensor element, 52 ... case, 53 ... heater, 55 ... electric wire connection Part, 60 ... cover, 61 ... fan cover, 65 ... sensor cover, 66 ... electric wire cover

Claims (16)

An internal combustion engine;
An exhaust pipe connected to the internal combustion engine;
A silencer disposed behind the exhaust pipe and connected to the exhaust pipe;
A fan disposed outside in the vehicle width direction of the internal combustion engine;
A fan cover disposed outside the vehicle in the vehicle width direction and having an opening formed therein;
A silencer cover arranged outside the silencer in the vehicle width direction;
A sensor element disposed inside the exhaust pipe and a heater for heating the sensor element; an oxygen sensor attached to the exhaust pipe;
The fan cover is formed integrally with the oxygen sensor and is located outward of the oxygen sensor in the vehicle width direction, and overlaps at least a part of the oxygen sensor in a side view of the vehicle. A sensor cover extending rearward,
The silencer cover is located on the outer side in the vehicle width direction than the oxygen sensor, and has a front portion extending outward in the vehicle width direction and rearward in the vehicle front-rear direction,
In the vehicle plan view, the distance in the vehicle longitudinal direction between the rear end of the sensor cover and the front end of the front portion of the silencer cover is the vehicle longitudinal direction between the rear end of the fan cover and the front end of the silencer. Saddle-type vehicle that is shorter than the distance.   2. The vehicle width direction inner end of the front portion of the silencer cover is positioned more inward in the vehicle width direction than an outer end of the sensor cover in the vehicle width direction in a vehicle plan view. Saddle riding type vehicle.   The saddle riding according to claim 1 or 2, wherein a front end of the front portion of the silencer cover is positioned inward in the vehicle width direction with respect to an outer end in the vehicle width direction of the sensor cover in a plan view of the vehicle. Type vehicle.   The front end of the front part of the silencer cover with respect to the vehicle front-rear direction is located at the same position as the rear end of the sensor cover or forward of the rear end of the sensor cover. A straddle-type vehicle according to any one of the above.   The straddle-type vehicle according to any one of claims 1 to 4, wherein the oxygen sensor is disposed behind the internal combustion engine. A rear wheel driven by the internal combustion engine,
The straddle-type vehicle according to any one of claims 1 to 5, wherein at least a part of the oxygen sensor is disposed at a position overlapping the rear wheel in a side view of the vehicle. A catalyst for purifying exhaust gas flowing through the exhaust pipe;
The straddle-type vehicle according to any one of claims 1 to 6, wherein the oxygen sensor is disposed downstream of the catalyst in the flow direction of exhaust gas.   The straddle-type vehicle according to any one of claims 1 to 7, wherein the sensor cover is disposed behind the opening of the fan cover. The oxygen sensor has a cylindrical case located outside the exhaust pipe,
The vehicle front-rear direction minimum distance between the sensor cover and the front part of the silencer cover in a vehicle side view is smaller than the dimension of the oxygen sensor in the axial direction of the case. A straddle-type vehicle according to any one of the above.   The vehicle sensor as viewed from the side, wherein the sensor cover is formed with a concave portion that is recessed forward, and the front portion of the silencer cover is formed with a convex portion that protrudes forward toward the concave portion. The straddle-type vehicle according to any one of 1 to 9. The oxygen sensor has a wire connection part,
The straddle-type vehicle according to any one of claims 1 to 10, further comprising an electric wire connected to the electric wire connecting portion.   The straddle-type vehicle according to claim 11, wherein the sensor cover overlaps with the electric wire connection portion of the oxygen sensor in a side view of the vehicle.   The wire cover that is integrally formed with the fan cover, is located outside in the vehicle width direction of at least a part of the electric wire, and overlaps at least a part of the electric wire in a vehicle side view. The straddle-type vehicle according to 11 or 12. The oxygen sensor has a sensor element located inside the exhaust pipe,
The straddle-type vehicle according to any one of claims 11 to 13, wherein the electric wire connection portion is disposed above the sensor element in an upper and lower direction of the vehicle and inward in the vehicle width direction.   The said electric wire is arrange | positioned inside the said vehicle width direction rather than the said fan and the said fan cover, and has an electric wire part extended toward the front, The any one of Claims 11-14. Saddle riding type vehicle.   The straddle-type vehicle according to any one of claims 1 to 15, further comprising a radiator disposed between the fan cover and the fan.

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